Is it permissible to take food from a person whose wealth is entirely from riba (usury or interest), who abandons prayer, and not eat it for fear that he will become averse to advice?

Question:
May Allah reward you, Honorable Shaykh. This questioner says: It is well known that it is not permissible to eat the food of one whose wealth is entirely from riba (usury or interest). And I, Honorable Shaykh, am afflicted by a neighbor who has this condition. He is neglecting the congregational prayer. I am trying to advise him and give him books and tapes, but I am in a dilemma regarding his food. If I refuse it, it causes him to become averse and he does not accept the advice. The question is: Do I take his food and then not eat it, leaving it until it spoils, or what should I do?

Answer:
If you are certain that this food is from what is forbidden, do not take it. Say that you are excused because you do not need it, or find an excuse. As for taking it and leaving it to spoil, no, do not take it. If you take it while knowing it is from riba (usury or interest), this encourages you to continue in riba (usury or interest) and makes you say that you take and eat, even if in some things you did not take. So, your leaving it is what leads him to repent to Allah the Exalted. If you take it, he may become more reassured in what he is doing.